Numerous portable electronic data acquisition means exist today. They include, for example, programmable digital computers, bar code scanners and readers, radio frequency communication tags and storage means, and digital and analog electrical input readers. Each of these devices addresses specific types of data input, such as electrical or electronic readouts from measuring or monitoring equipment, test equipment or keyboard input, optical scanners or radio frequency devices.
While many of these input devices are portable, they are limited to the specific type of data or data input mechanism used to acquire data. For example, bar code scanners can read data from a bar code and provide conversion for down loading into a computer or like means. General purpose computers, on the other hand, are limited to keyboard inputs which are ideal for inputting large amounts of data at a fixed location.
With the advent of lightweight portable computers, the ability to collect and analyze data at different locations has been greatly enhanced. However, the limitation of keyboard input reduces the effectiveness of such devices for certain data acquisition purposes. In particular, employment of portable, general purpose computers has not been successful for obtaining routine or repetitive types of field information at manufacturing processes, distribution locations, hospitals or the like or where the individuals required to use the computer are not skilled. To overcome some of these limitations, pen-based general computers have been introduced which permit input of data through a digitizer and "pen." The "pen" is used to activate the digitizer to produce handwritten, strike-based characters. These computers include character recognition algorithms which convert the handwritten input into computer recognizable data. These devices attempt to follow the paradigm of paper and pencil input which is particularly useful for those not skilled in keyboard input. However, to date, such devices have been of only limited success.
Generally, pen-based computers are designed to replicate the functions of general purpose programmable computers using a "pen" as the input means, rather than a keyboard. As such, these devices carry the overhead of a programmable digital computer, on-board memory storage and processing adapted to general purpose computing rather than data acquisition. Until only very recently, pen-based computers were not designed for efficient in-field data acquisition. See for example, the IBM's Thinkpad, Grid System's Grid Pad SL, NCR's, NCR 3130 Note Pad and Samsung's Penmaster. These computers are based on the Intel, 3865X or 386 SL microprocessor and weigh from 4.7 to 6.3 lbs.
A number of early devices have been designed to enhance in-field data acquisition by making them smaller and lighter to facilitate handling. However, these improved devices continue to function in the mode of a general purpose computer. They use the same microprocessors, general architecture and magnetic storage as general purpose microcomputers. Operating systems have been modified by reason of the change in input means and the need for character recognition, but basically, these improved pen-based computers are modified general purpose digital computers.
Accordingly, it is an object of the present invention to provide a portable data acquisition system which takes advantage of a pen-based input means, but without the disadvantages inherent in pen-based general purpose computers. It is a further object of the present invention to provide a data acquisition means having embedded process controllers and minimal on-board data storage. It is also an object of the invention to provide a data acquisition means which is portable, light weight and physically small to facilitate its use "in the field" using a powerful paper and pencil paradigm. It is also an object of the invention to provide a data acquisition means which is controlled by minimal code and on-board storage thereof and which is based on database rather than general data processing algorithms.